In the stabilization process there for instance may be included a method for a fast pre-heating to a temperature distribution in the product suited for a microwave treatment. A two-step process comprising a contact with a hot medium directly followed by a contact with a cooler medium does in this case precede the microwave treatment.
It is also possible to adjust the temperature profile in advance such that the microwave treatment gives a uniform temperature profile within the product.
A further possibility is to carry out the microwave treatment in water or other liquid and in such case control the water temperature so that the tendency of increased surface temperature is suppressed.
A heat stabilization according to the present concept implies a qualified process technology and it is of utmost importance that the physical conditions for the stabilization/process are the proper ones.
The problem of the invention is to provide a device that allows a sophisticated process handling of products packed in a flexible packaging material. It should for instance be prevented that the product dissipates vapour and expands (blows up) and it is also necessary to transport the product into and out from a pressurized zone. Furtheron, it is of importance to get a uniform, fast heating whereby a uniform maximum thickness of the product is especially important for products lacking specific form as stews and for products that tend to change their form when heat treated, for instance slices of meat. It is also of importance that the end product obtained in the system is a product which is suited for rational packaging and cartonning systems.